CN102644505A

CN102644505A - Method for operating turbocharger arrangement and control unit for turbocharger arrangement

Info

Publication number: CN102644505A
Application number: CN2012100412587A
Authority: CN
Inventors: S·彼德洛维奇; A·M·R·施瓦利尔; A·巴奇
Original assignee: Ford Global Technologies LLC
Current assignee: Ford Global Technologies LLC
Priority date: 2011-02-21
Filing date: 2012-02-21
Publication date: 2012-08-22
Anticipated expiration: 2032-02-21
Also published as: CN102644505B; US9181857B2; EP2489851B1; EP2489851A1; US20120210711A1

Abstract

The present invention relates to a method for operating a turbocharger arrangement of an internal combustion engine, the turbocharger arrangement comprising a low-pressure and a high-pressure turbocharging stage arranged sequentially, the high-pressure turbocharging stage comprising a high-pressure compressor with a sensorless compressor bypass valve, comprises evaluating at least one sensor signal of the turbocharger arrangemen for detecting a failure mode of the compressor bypass valve.

Description

Be used for operating turbine pressurized machine equipment and the method that is used for the control unit of turbocharger apparatus

The cross reference of related application

The title that the application requires on February 21st, 2011 to submit to is the preference of the european patent application No.11155170.1 of " Method for Operating a Turbocharger Arrangement and Control Unit for a Turbocharger Arrangement ", and its full content is herein incorporated for your guidance.

Background technique

Explosive motor, particularly DENG and petrol engine often are equipped with turbosupercharger.Usually, turbosupercharger is driven by the blast air of explosive motor and is placed in one.Blast air and/or inlet stream are by one or more bypass valve control in the tributary that is arranged in exhaust and/or gas handling system; And guarantee to consider various constraint conditios; Comprise exhaust gas composition, compressor exit temperature and turbine-entry temperature, and avoid turbo-charger surge or hypervelocity.Usually had perhaps " failure safe " position of acquiescence by the bypass valve of ACTIVE CONTROL, when not having vacuum or power supply device its move to this position.The failure safe position is opened fully usually or is closed fully.Default setting is confirmed by the factor that for example pinnacled safety and engine power require.Yet compressor bypass valve also can lose efficacy and be stuck in position for example closed fully or that open fully.Expectation detects this fault of compressor bypass valve, and does not need the cost and the complexity of the increase of position feedback transducer and association thereof.

Summary of the invention

The invention discloses the turbocharger apparatus and the method that is used for the control unit of this turbocharger apparatus that are used to move explosive motor.Explosive motor comprises the multistage order turbocharger apparatus that comprises low pressure stage and high pressure stage.The blast air of explosive motor and/or inlet stream are by one or more bypass valve control in the tributary that is arranged in exhaust and/or gas handling system, and it is parallel to the turbine and/or the compressor of turbosupercharger separately.In order to reduce cost and complexity, bypass valve is passive, and owing to the pressure difference of passing them opens or closes.Owing to do not have ACTIVE CONTROL or position feedback transducer, other sensors to be arranged on a plurality of positions in the motor, thereby measure signal and the parameter that influenced by the bypass valve operation.Signal and/or parameter can comprise air mass flow, boost pressure, inter-stage temperature and back compressor temperature.

The present invention further provides the method that is used to compensate bypass valve defective.The control unit that is connected to a plurality of sensors through link can receive the state of measured value and the operation of definite bypass valve.Then, control unit can be through the overall operation of control member actuator management turbocharger apparatus.Therefore, if bypass valve defective, control unit can compensate and keep normal motor operation so.

Description of drawings

Fig. 1 illustrates the part of explosive motor, and it comprises turbosupercharger, compressor bypass valve, control unit and a plurality of links between sensor and control unit.

Fig. 2 illustrates the diagrammatic representation of the position of turbocharger speed dependence compressor bypass valve in the example scenario.

Fig. 3 illustrates the initial part of the method that is used to detect the compressor bypass defective valve.

Fig. 4 illustrates and is used to detect the method at high rotating speed and/or torque range inner compressor bypass valve defective.

Fig. 5 illustrates and is used to detect the method at the slow-speed of revolution and/or torque range inner compressor bypass valve defective.

Fig. 6 illustrates the method for operation explosive motor when the compressor bypass valve function is normal.

Fig. 7 illustrates the method for operation explosive motor when the compressor bypass valve functional fault.

Embodiment

In the embodiment that Fig. 1 schematically illustrates, explosive motor 1 illustrates the multistage order turbocharger apparatus that comprises high pressure turbocharger 3 and low pressure turbocharger 4.High pressure turbocharger 3 is used for satisfying the back pressure requirement that is used to drive exhaust gas recirculatioon, and it comprises high-pressure turbine 5 and high pressure compressor 6, and compressor 6 is driven by turbine 5 via transmission shaft 7.Low pressure turbocharger 4 is used for peak power, and it comprises the low-pressure turbine 8 that drives low pressure compressor 9 through transmission shaft 10.

Turbine

5 and 8 sequentially is arranged in the vent systems 11 of explosive motor, and high-pressure turbine 5 is arranged on the upper reaches of low-pressure turbine 8, promptly at the higher section of pressure.Correspondingly, compressor 6 and 9 sequentially is arranged in the gas handling system 12 of motor 1, and high pressure compressor 6 is positioned at the downstream of low pressure compressor 9.Blast air direction in airflow direction in the gas handling system 12 and the vent systems 11 is respectively by

arrow

13 and 14 indications.Interstage cooler 21 is arranged on the downstream of high pressure (HP) compressor.Usually, high-pressure turbine 5 and high pressure compressor 6 are respectively less than low-pressure turbine 8 and low pressure compressor 9.This is schematically illustrated in Fig. 1.

High-pressure turbine bypass valve 15 (TBV) is provided with in the parallel branch of the vent systems parallelly connected with high-pressure turbine 5.Therefore, high pressure TBV 15 all or part of opened and made and be used for the bypass segment of blast air or all walk around high-pressure turbine 5.If blast air partially or fully passes bypass valve 15, therefore high-pressure turbine 5 is driven with the speed that reduces so.Therefore, the operation of high pressure turbocharger 3 can be by the operation control of TBV 15.In a similar fashion, low pressure TBV 16 is arranged in the parallel branch of the vent systems 11 parallelly connected with low-pressure turbine 8.Low pressure TBV 16 also is represented as " wastegate " (WG).WG 16 moves on one's own initiative, serves as actuator, and can comprise or not comprise position feedback transducer.

In gas handling system 12, inlet stream is crossed low pressure compressor 9, is compressed in the phase I of compression.Thereafter, inlet stream is crossed high pressure compressor 6, and the second stage of expression compression perhaps flows through the parallel branch with high pressure compressor 6 parallelly connected settings.Parallel branch can be opened or closed by compressor bypass valve 17 (CBV).CBV 17 is passive, promptly by the pressure difference operation through its effect, and does not comprise position feedback transducer.Especially, 17 of CBV have two positions of opening fully with closed fully.

The state of compressor bypass valve 17 has direct or indirect influence to the various parameters of the operation of decision turbocharger apparatus 2.For example, pressure ratio that is provided by high pressure compressor 6 and the flow through gas handling system 12 are because opening or closing of CBV 17 and being changed significantly.In addition, the speed of high pressure turbocharger 3, the boost pressure that provides by turbocharger apparatus 2 and many other parameters influence of receiving the function of CBV 17.Therefore, these parameters can be used in the inefficacy that detects CBV 17.

Charge flow rate, boost pressure and/or compressor exit temperature can be measured by the downstream sensor shown in the symbol among Fig. 1 18.In this example, downstream sensor 18 is positioned at high pressure compressor 6 and 23 downstream, high pressure compressor bypass tributary.Yet downstream sensor 18 can be positioned at other positions of air inlet duct.Replacedly, additional sensor can be provided, and can provide one for each quantity of wanting to measure.Motor 1 can comprise other sensors, comprises the inter-stage sensor 19 that can measure inter-stage boost pressure and/or temperature, low pressure turbocharger sensor 20 and high pressure turbocharger sensor 21 between low pressure compressor 9 and high pressure compressor 6.As previously mentioned, two sensors can be set replace inter-stage sensor 19, each is respectively applied for measures inter-stage boost pressure and inter-stage temperature.Preferably, directly measure the back compressor temperature in the downstream of high pressure compressor 6.Low pressure turbocharger sensor 20 can be measured its turbocharger speed separately with high pressure turbocharger sensor 21 boths, and can place many positions with respect to its turbosupercharger, is included in turbine, compressor or transmission shaft place.In addition or replacedly, if sensor maybe be unavailable, turbocharger speed can be measured through using corresponding compressor map so.Explosive motor 1 also can be equipped with exhaust gas recycling system, and it does not illustrate in Fig. 1.

A plurality of

sensor links

22,24,26 and 28 are shown in Fig. 1, and it allows to be sent to by the measured value that sensor obtains and is used to the control unit 100 handling and analyze.Disclosed like the front, motor 1 can comprise additional sensor, in this situation, the additional sensor link will be provided.

Control unit 100 is shown microcomputer commonly used in Fig. 1, it comprises: microprocessor unit (CPU) 102, input/output end port (I/O) 104, ROM (read-only memory) (ROM) 106, random-access memory (ram) 108, keep-alive storage (KAM) 110 and conventional data bus.The mechanized data programming of the instruction that storage medium ROM (read-only memory) 106 can enough expressions can be carried out by processor 102, these instructions are used to carry out method and other variants desired but that specifically do not list that are described below.Control unit 100 further comprises and is used for through handling the output unit of low pressure TBV 15 and high pressure TBV 16 control turbocharger apparatus 2.Valve can be handled by vacuum or electrical signal.Through controlling these actuators, control unit 100 can mesh first and second control modes---and one is used for specified CBV operation and one and is used for CBV and lost efficacy.Control unit 100 also can comprise the signal output apparatus that is used for warning sign and be used to store the dead-file about the information of detected failure mode.Control unit can be the portions of electronics control unit of motor.Control unit 100 receives signal via the sensor link that is attached to explosive motor 1 from the sensor shown in Fig. 1.

Fig. 2 illustrates the illustrative example (per minute 1000 revolutions) of the turbocharger speed of high pressure turbocharger 3 (curve 40) relevant with the position CBV pos of CBV 17 and low pressure turbocharger 4 (curve 42), and the position of CBV 17 provides as its mark of opening fully.As shown in Figure 2, the speed 40 of high pressure turbocharger 3 significantly rises with the opening degree of CBV 17, and the speed 42 of low pressure turbocharger 4 is irrelevant with opening of CBV basically.On the contrary, the speed 40 of high pressure turbocharger 3 allows to detect opening of CBV 17.Although CBV 17 only has two positions usually, Fig. 2 illustrates in principle also can confirm the neutral position.Therefore, if CBV 17 open fully or fully operating position or even block in the neutral position, this can detect through the rotating speed of measuring high pressure turbocharger 3.Particularly, can setting threshold, rotating speed surpasses threshold value indication CBV 17 to be opened fully, and it is closed fully that rotating speed is lower than threshold value indication CBV 17.In example shown in Figure 2, and for the setting of the parameter that adopts in this situation, be used to distinguish closed fully the threshold value of CBV with the state of opening fully can be set in about 60,000rpm.

Fig. 2 is illustrated in the measurement that low relatively engine speed (2000rpm) is carried out.Under this engine speed, the reliable detection that the rotating speed of high pressure turbocharger 3 can allow CBV to lose efficacy.For given compressor pressure ratio, total air mass flow also allows to confirm the CBV position.Because also can there be the little decline of boost pressure in the opening of CBV 17.Other parameters, for example compressor efficiency, compressor exit temperature or compressor pressure comparison CBV state are more insensitive.

Fig. 3 illustrates the initial part that is used to detect the method 300 that CBV lost efficacy.At step 302 place, method begins and can in real time or disperse employing at interval, so that CBV by continuous monitoring, lost efficacy thereby detect as early as possible.Control unit 100 receives at least one sensor signal of indicating CBV 17 situation or turbocharger apparatus 2 via the sensor link, can derive the physical parameter and/or the error flag of indication turbocharger apparatus 2 thus.Replacedly or in addition, can adopt appropriate sensor, it directly is provided to control unit with physical parameter, rather than needs the signal of extra process.Compare with sensor signal, physical parameter can provide the difference quantity that increases between the CBV state of normal CBV state and inefficacy, allows to have the measurement that is easier to of the bigger degree of reliability.The example of sensor signal is described with reference to Figure 4 and 5.

At step 304 place, control unit 100 can filter at least one sensor signal before whether definite CBV 17 had lost efficacy.Filtration can comprise the time domain lower pass-filter, and is used for avoiding owing to comprise noise or close or the wrong detection of transition state on the contrary time the former thereby the inefficacy that causes from opening to change to when the position of CBV 17.Can filter the physical parameter or the function of the pattern of expression CBV equally.This function derives through at least one sensor signal of assessment, and can be indication CBV 17 state parameter or indicate the parameter or the error flag of the inefficacy of CBV 17.In one embodiment, according to the fully closed or valve state opened fully respectively or whether detect valve invalidation, this function can adopted value 0 or 1.

At step 306 place, this method is confirmed engine working point, and it can be a characteristic with engine speed and/or load.The concrete mode that engine working point is described can depend on the calibration of motor and the characteristic of engine components and turbocharger apparatus 2.Because measured quantity and the result action difference between each operation point, so comprise confirming of engine working point.If motor is confirmed as in low operation point, promptly be in the slow-speed of revolution and/or have underload, therefore this method proceeds to Fig. 4 so.On the contrary, if motor at high rotating speed and/or have heavy load operation, therefore this method proceeds to Fig. 5 so.

If engine working point is high, this method is as shown in Figure 4 so continues at step 402 place.Owing to comprise various sensors, so a plurality of signal and parameter can be available, this method can be used the situation of these signals and parameter evaluation CBV 17.Yet some signal and parameter can be responsive more to the CBV situation in concrete operation point.Under the engine speed of 3500RPM, for example, air mass flow can be the most responsive to the CBV situation.Therefore, in the high-engine operation point, method 400 is at first assessed air mass flows at step 404 place with downstream sensor 18.Before assessment, can proofread and correct air mass flow for the air-flow that passes high pressure compressor bypass tributary (for example 23 among Fig. 1).If control unit 100 confirms that air mass flows are in maximum value, promptly air-flow gets clogged, and the CBV operation was lost efficacy probably so, and this method proceeds to step 414 and sentences compensation and lost efficacy.If air-flow does not block, this method proceeds to step 416 and sentences and guarantee normal operation so.In the embodiment shown in fig. 4, if be not sure of the air mass flow situation, this method provides action so.In this situation, this method proceeds to step 406 place, assesses next most preferred sensor signal or physical parameter here, thereby confirms the CBV situation.Here, this method is checked the loss whether boost pressure takes place with downstream sensor 18.In other embodiments, this method no matter result of step 404 proceeds to step 406 from step 404, continues to accomplish up to all sensors signal and/or physical parameter assessment.Further, can only assess the child group of available signal and/or parameter.In this embodiment, consider all possible data, so that increase the degree of reliability and the determinacy of CBV assessment of scenario.

Assumption method 400 is not assessed the CBV situation at last; Perhaps further measurement signal and/or parameter have been selected so that increase the degree of reliability; This method proceeds to step 408, and wherein inter-stage sensor 19 is used between evaluation stage boost pressure and temperature between step 410 evaluation stage.The threshold value that is used for inter-stage boost pressure and temperature is set the boundary between specified CBV operation and the inefficacy.These values can be confirmed or calculating at the motor run duration in advance.

At step 412 place, this method adopts downstream sensor 18 to confirm whether the downstream temperature of high pressure compressor 6 has surpassed its threshold value separately similarly.If surpass its threshold value separately step 408,410 and 412 places one or all measurment, this method proceeds to step 414 place so, and wherein CBV lost efficacy and compensated.On the other hand, if CBV is determined normal operation, method 400 proceeds to step 416 place so, in step 416, adopts first control mode, and is as shown in Figure 6.

If engine working point is low, when promptly motor operated in the slow-speed of revolution and/or has underload, initial methods 300 proceeded to method as shown in Figure 5 500 from step 310, thereby confirmed the CBV situation similarly.

At step 502 place, the method that is used to detect the CBV situation begins.At first assessment has the speed of the high pressure turbocharger 3 of high pressure turbocharger sensor 21 to method 500 at step 504 place, and high pressure turbocharger sensor 21 can be placed in turbine, compressor or transmission shaft place separately.Replacedly or in addition, can use compressor map.As previously mentioned, this method can be directly to step 510 or step 512, and response CBV situation, and perhaps this method can proceed to step 506 and arrive step 508 then.In step 506, downstream sensor 18 is used to detect air mass flow and whether is lower than threshold value.In step 508, downstream sensor 18 also is used to detect the loss of boost pressure.Notice that at high-engine operation point and low engine working point, the loss of boost pressure can indicate CBV to lose efficacy.Should be appreciated that sensor signal listed in the method among Fig. 5 and physical parameter only are illustrative, and should not be in and limit the disclosure in any case.More specifically, in Fig. 5 listed, extra sensor signal and/or physical parameter can be used to assess the CBV situation, comprise interstage pressure, inter-stage temperature and back compressor temperature.

After any one completion of method 400 or method 500, normal, so as shown in Figure 6 if the CBV operation is confirmed as, adopt first control mode at step 602 place.In step 604, like the step 306 among Fig. 3, engine working point is determined.For low operation point, method 600 proceeds to step 606 place, and low pressure TBV is closed fully at step 606 place.Then, at step 608 place, with high pressure TBV control boost pressure.Yet, be to be understood that and can adopt additive method control boost pressure.In step 610, because pressure difference, CBV 17 is closed fully.In step 618, this method 600 can optionally or replacedly be set to best position with low-pressure turbine valve and high-pressure turbine valve, and this depends on the current location of current motor and/or load and CBV.Its position can be in complete closure and the neutral position between opening fully.This means and carry out the closed loop control of adopting low-pressure turbine valve and high-pressure turbine valve.With this mode, the optimum performance in the slow-speed of revolution/torque range can be provided, and the needed back pressure of exhaust gas recirculatioon.

If engine working point is confirmed as height, method 600 proceeds to step 612 from step 604 so, and its mesohigh TBV opens fully.Next, in step 614, with low pressure TBV control boost pressure, and in step 616, CBV opens fully.With this mode, the peak value engine power can be provided.As previously mentioned, this method can optionally or replacedly be set to best position with low-pressure turbine valve and high-pressure turbine valve, and this depends on the current location of current motor and/or load and CBV.

Ending in

method

400 or 500 was lost efficacy if CBV is confirmed as, and operation proceeds to second control mode as shown in Figure 7 so.Through adopting second control mode, motor can be regulated inefficacy safely, and can obtain maximum responsiveness and power and/or minimum pollutant emission in addition.Method 700 begins at step 702 place, and at step 704 place, like the step 306 among Fig. 3, confirms engine working point.Should confirm that if the operation point is high, then this method proceeds to step 706, its mesolow TBV is closed fully.Control boost pressure at step 708 place with high pressure TBV then.Then, the input/output end port 104 (Fig. 1) at step 710 place via control unit 100 sends the inefficacy alarm to the vehicle operating personnel, and this inefficacy can be recorded in the storage of control unit 100.In step 720, method is accomplished, and can get back to step 302 among Fig. 3 to repeat as required.

On the contrary, low if engine working point is confirmed as, method 700 proceeds to step 712 so, and its mesohigh TBV opens fully.Then, in step 714, with low pressure TBV control boost pressure.Then, as previously mentioned, method proceeds to

step

710 and 716, the operations staff of notice vehicle lost efficacy and with failure logging (record) in storage.In step 720, method is accomplished, and can get back to step 302 among Fig. 3 to repeat as required.

Claims

1. method that is used to move the turbocharger apparatus of explosive motor; Said turbocharger apparatus comprises low-pressure turbine booster stage and the high-pressure turbine booster stage that order is provided with; Said high-pressure turbine booster stage comprises the high pressure compressor with no sensor compressor bypass valve; Said method comprises at least one sensor signal of assessing said turbocharger apparatus, is used to detect the failure mode of said compressor bypass valve.

2. method according to claim 1, wherein said at least one sensor signal are the signals of expression inlet air flow, boost pressure, interstage pressure, inter-stage temperature, back compressor temperature or turbocharger speed.

3. method according to claim 2; Wherein said at least one sensor signal is used for confirming at least one physical parameter of said turbocharger apparatus by assessment, and said at least one physical parameter is distinguishing with respect to the operating mode of said compressor bypass valve.

4. method according to claim 3, said at least one physical parameter of wherein said turbocharger apparatus are compressor airflow, compressor pressure ratio, turbocharger speed, compressor efficiency or compressor exit temperature.

5. method according to claim 4, said at least one sensor signal of wherein said turbocharger apparatus (2) is used for detecting according to engine working point the failure mode of said compressor bypass valve by assessment.

6. method according to claim 5 is wherein filtered said at least one sensor signal of said turbocharger apparatus and the function of said at least one physical parameter and the operating mode of the said compressor bypass valve of expression.

7. method according to claim 6, wherein said at least one sensor signal is assessed at the run duration of said explosive motor continuously, is used to detect the failure mode of said compressor bypass valve.

8. method according to claim 1, wherein said turbocharger apparatus is moved according to first control mode, and according to the detection of the failure mode of said compressor bypass valve, said turbocharger apparatus is moved according to said second control mode.

9. method according to claim 8; Wherein said first control mode is the slow-speed of revolution/torque control mode; And in said second control mode, said high-pressure turbine bypass valve is set to fully to be opened, and boost pressure is controlled by said low-pressure turbine bypass valve.

10. method according to claim 8; Wherein said first control mode is high rotating speed/torque control mode; And in said second control mode, said low-pressure turbine bypass valve is set to complete closure, and boost pressure is controlled by said high-pressure turbine bypass valve.

11. a method comprises:

Operation has the low pressure turbocharger that order is provided with and the motor of high pressure turbocharger, and said high pressure turbocharger comprises the compressor that to have no sensor compressor bypass valve be CBV;

Indicate the degradation of said CBV according to Operational Limits; With

Degradation in response to said compressor bypass valve is regulated operation.

12. method according to claim 11, wherein said turbosupercharger is moved according to first control mode, and according to said indication, said turbosupercharger is moved according to second control mode.

13. method according to claim 12; Wherein said first control mode is the slow-speed of revolution/torque control mode; And in said second control mode, the high-pressure turbine bypass valve is set to fully to be opened, and boost pressure is controlled by the low-pressure turbine bypass valve.

14. method according to claim 12; Wherein said first control mode is high rotating speed/torque control mode; And in said second control mode, the low-pressure turbine bypass valve is set to complete closure, and boost pressure is controlled by the high-pressure turbine bypass valve.

15. a method comprises:

Operation has the low pressure turbocharger that order is provided with and the motor of high pressure turbocharger, and said high pressure turbocharger comprises the high pressure compressor that to have no sensor compressor bypass valve be CBV;

In response to the degradation of CBV under the slow-speed of revolution/moment of torsion, the high-pressure turbine bypass valve is set at opens fully and by low-pressure turbine bypass valve control boost pressure; With

In response to the degradation of CBV under high rotating speed/moment of torsion, said low-pressure turbine bypass valve is set at complete closure, and by said high-pressure turbine bypass valve control boost pressure.